watkeys



A. A. 3. n@ 7 Aw 11 S Y E K T A W L TU 2 9 11 COOLING STILL Filed Nov.22 1921 35u LX y 977 Patented Dec, l, 1923.

THOMAS WATKEYS, 0F PORT ARTHUR, TEXAS, ASSIGNOR TO GULF REFINING COM-PANY, OF PITTSBURGH, PENNSYLVANIA, A. CORPORATION OF TEXAS. 4

COOLING STILL Application led November 22, 1921. Serial No. 517,022.'

To all whom t may cmwem:

Be it known that I, THOMAS L. WATKEYB, a citizen of the United States,residing at Port Arthur, inthe county of Jefferson and State of Texas,have invented certain new and useful Improvements in Cooling Stills, ofwhich the following is a specification.

This invention relates to cooling stills; and it comprises a method oflcooling stills which have been used for the production of gasoline andthe like from higher boiling oils with the aid of aluminum chlorid andwhich contain exhausted aluminum chlorid residues, wherein hot residualoil in the still is displaced by cooler oil and the still is Hooded withcold high boiling oil-'until it is cold or nearly so; all as more fullyhereinafter set forth and as claimed.

In the manufacture of gasoline and other low boiling oils from higherboiling oils, one of the processes now in useis to heat the hi h boilingoil with anhydrous aluminum chIorid. In so doing, the high boiling oil,gas oil, for example, enters into ebul ition at a temperature below. itsnormal boiling point, giving vapors of lower boiling oils, such asgasoline. By the use of proper methods, large yields of gasoline can bemade in-this way from various high boiling oils. After a time, thealuminum chlorid loses its activity and becomes converted into a tarryor coky mass. By the use ofvarious expedients, itis possible to removethis residue from the still in greater part, and continue the opera-tionwith the addition of fresh aluminum chlorid; but after a time, it isnecessary to stop the distillation and cool down the still for cleaning.Sometimes theoperation is intermittent and the still is cooled downafter the use of a single charge of chlorid. As these Aoperations areordinarily carried out in large apparatus units, the cooling down offersconsiderable difficulty. The expedient in use with coking s'tills andthe like of blowing in steam for cooling is not here practical, for thereason that steam instantly produces hydrochloric acid from theseresldues. And with a 1000 barrel still, bricked up in the usual way andheat insulated, natural cooling after dlscontinuance of firing may takea weeks time.

It is the object of the present invention to provide a simple andeconomical way of quickly cooling stills of this ty in the use ofaluminum chlorid, distillation As stated, I

is continued until the aluminum chlorid residues have substantially nofurther converting activity upon oil. Such being the case, it ispracticable in cooling one of these stills to produce a flow 'of coldoil through it until the Whole apparatus is cooled to the desiredtemperature. In practice I first draw ofl' the aluminum chlorid sludgeor coky residue and then displace the hot oil in the still with cooloil, so that the temperature ofthe hot oil in the still is graduallylowered, and I remove the oil from the still which is being cooled andsendit advantageously through cooling coils and thence back to the stillor to the stock tank. I may deliver cool oil toward the bottom of thestill v to be cooled and send the removed oil from vantageously such asis used in the distilla-4 tion of higher boiling hydrocarbons withanhydrous aluminum chlorid for the production of lower boilinghydrocarbons. stills are usually provided with stirring mechanism, theshaft of which is shown at 2, driven vby gear 3., in turn driven bpinion or worm on sha-ft 4, supported by brackets 5, and driven bypulley wheel 6. The chargle of oil, or oil and aluminum chlorid, is amitted at 7 and residual oil and aluminum chlorid sludge or residue maybe removed through pipe 8. The still -is equipped with vapor line 9leading to the coolers. The still may be fired by fire box 10. Thisconstruc-v tion forms no part of my invention.

After operating` the aluminum chlorid process for some time, it isnecessary to clean out the stills, or it may be necessary to repairthem. Before this can,be done, the stills must be reduced to atemperature sufliciently low to permit entrance of workmen. Assumin thatthere has been an valuminum chlorid distillation performed in the still,the heavy aluminum chlorid sludge 0r coky residue may be withdrawnthrough pipe 8. There will then remain in the still.

a considerable portion of hot unconverted Suchv l higher boiling oil.Higher boiling oil from f the oil stock tank 11 may then be sent to thestill by means of the pump. 12 by means of the Valved line 13 enteringat `a low point in the still and the hot oil in the still is displaced,owing out near the top of the still through valved line 14, either tothe cooler 15 through valved line 16 or back to the stock tank throughvalved line 17. lf the oil is sent to the cooler 15, it may be cooledtherein by `means of water or the like flowing in at 18 and out at 19,and may then be sent. to the pump l2 by means of the valved line 201 Orthe oil may be sent from the cooler directl to the stock tank 11 b meansof Jthe va ved line 21. Or the 011 displaced from the still 1 throughthe line 14 may be sent directly to the stock tank 11 by means of line17, more cold oil from the bottom ofthe tank being sent to the stillthrough theiline 13. l

With the arrangement described it is therefore possible to displace thehot oilin the still by cold oil from the stock tank, or

cold oil from thel cooling coil, and to gradually lower the temperaturein the still.

With my process l have been able to lowerthe temperature in the stillwithin 12 hours to a point permitting entrance of workmen; whereas, whenthe still is allowed to cool in the usual way, a coolin period of a weekor more is necessary. articularly in the aluminum chlorid stills, it isnot lpossible to cool by means of steam, because the aluminum chloridused in these stills must ge anhydrous and the stills mustbe kept lllmayl constantly feed in some fresh cold oil from the stock tank whileleadin in cold oil from the cooling coils. And if esired l may reversethe How, su plying cold oil at the top of the still and withdrawing thehot oil from below.

What l claim is 1. The process of cooling hot stills used in treatingoils with a catalytic agent which is rendered ineHicient by contact withwater which comprises discontinuing the distillation and displacing thehot residual oil in a still with cooler oil.

2. rEhe process of cooling hotl stills used in treating oils .with acatalytic agent which is rendered ineiiicient by contact with waterwhich comprises discontinuing the distillation anddisplacing the hotresidual oil in a still with cooler oil, coolin the displaced oil whichhas become heate and usin it for cooling the still and displacing therst used oil.

3. The process of cooling hot stills used 1n treating oils with acatalytic agent which is rendered ineiiicient by contact with watercontaining hot residual oil which .comprises discontinuing thedistillation, adding cooler oil to the still, withdrawing the mixtureand sending it back to the still.

. 4. The process of `cooling hot stills used 1n treating oils with acatalytic agent which is rendered inelicient by contact with watercontaining hot residual oil which comprises discontinuin thedistillation, adding cooler oil to the sti l, withdrawing the mixtul-i,cooling it and sending it back to the s 1 y 5. The process of coolingstillsv used in treating o1ls with a catalytic agent which is renderedineilicient by contact with water containing residual hot oil whichcomprises discontinuing the distillation, displacing the hot oil in thestill by meansofcooler oil, cooling the hot oil in cooling apparatus andreturning it to the still.

6. The process of cooling stills used in treating oils with a catalyticagent which is rendered inelicient by contact with water which comprisesdiscontinuing the distillation and displacing hot oil therein by4constantly circulating cooler oil.

ln testimony whereof, l have hereunto aiixed my signature.

THMAS L. WATKEYS.

